# Calculus

Find the integral by substitution

∫ [(16 x3)/(x4 + 5)] dx

∫[ 4 x/(√{x2 + 3})] dx

∫ 8 x2 e4 x3 +7 dx

1. 👍 0
2. 👎 0
3. 👁 121
1. Hints:
1. if u=x4+5
du/dx
=d(x4+5)/dx
=4x³
or du = 4x³ dx

2. u=√{x² + 3}
du/dx = x/√{x² + 3}
du = xdx/√{x² + 3}

3. u=?
8x²e4/(x³ +7)

1. 👍 0
2. 👎 0
posted by MathMate

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